Her stomach felt sick. The only thing she could think about was home. Her friends, her school, her own house. Her parents. She never knew that being homesick made you literally sick. She typically wasn't one to be sad, she was just the one who was constantly making jokes and running around so that no one would try to look any deeper.

Yet even now, her pillow was damp with the tears of several months that hadn't had a chance to escape. She never cried. It felt wrong somehow. She was scared someone would come in and see, but she had the door locked and music playing so that if anyone tried, she would play it off as forgetting she locked it, and that would give her enough time to get herself in order.

She couldn't think of a valid reason why her homesickness was a secret, but she couldn't bring herself to tell anyone. She just wasn't the type. She never cried.

What was that? She held her breath. Someone stomping quickly up the stairs. Then that familiar creaking of the hallway floorboards, then a key in a lock, a door opened and then slammed shut. The girl in the room next door? What was her name, Sammy? Tammy? She rolled over to face the wall, listening. Her eyes naturally focused on the photo of Mum and Dad she’d pinned there. Perpetually at the theme park wearing stupid hats; she remembers that day as if it were yesterday. Just the three of them, a spur-of-the-moment decision because Dad had said he was bored. Then the wall spoke to her, a series of pitiful sobs – muted by a pillow? She chewed her bottom lip and wondered what must have happened to her? Had she heard my sobs too?

The sobbing didn't stop.

She lay there for what felt like an hour but was probably four minutes, staring at the photo of Mum and Dad in their stupid hats, telling herself it wasn't her business. People were allowed to cry in private: she, of all people, understood that. She couldn’t stand the sound nevertheless. The muffled crying, with a pillow pressed to the face, breath coming and going in shudders. It was the sound she had made herself, just an hour ago, and no one had come.

She sat up. The mattress springs squeaked and she froze, as if the girl next door might hear and know she'd been listening. The sobbing hitched, then carried on.

Don't be weird, she told herself. You don't even know her name.

In the hallway the floorboards creaked under her socks, exactly the way they had when the girl had stormed past. She stopped outside the door with the little brass number 6 hanging slightly crooked. A strip of yellow light glowed along the bottom. Up close, the crying was worse. She raised her hand to knock and stopped. What was she supposed to say? She was good at jokes, at filling a room with noise so nobody could see past it. Only, a joke felt like the worst possible thing to make in this situation.

She knocked. The crying cut off like a tap being turned.

"Sorry," a thick voice said. "Am I being too loud?"

"No!" It came out too fast. She winced. "No, not at all. I just... I live next door. I wanted to check you were okay. You don't have to say. I mean, you can say. Or not." She closed her eyes, cringing at herself.

Unexpectedly, a wet little laugh from the other side of the door.

"That was really bad," the voice said.

"I know. I'm usually funnier."

"Are you?"

"Sometimes. It's sort of my whole thing."

The lock clicked. The door opened a few inches, and a face appeared: blotchy, red-eyed, dark hair stuck to one cheek. She looked about the same age. She was clutching a pillow like a shield.

"Tammy," she said, sniffing again. "Not Sammy. I heard you through the wall earlier, trying to work it out. Sorry. These walls are made of paper."

Emily stared at her. So Tammy had heard her too.

Heat rushed up her neck. "You heard that?"

"Just a bit." Tammy's voice was careful. "I thought you wouldn't want me to say anything."

"I never cry," Emily said. It sounded ridiculous out loud. "Like, never. I don't know what that was."

"I think it was crying," Tammy said gently.

"Yeah." She let out a shaky breath, and to her horror her eyes stung again. "Yeah, I think it was."

Tammy opened the door the rest of the way and stepped back. Behind her the room was a mirror of Emily's own, same narrow bed, same beige curtains, but the walls were bare, and a half-unpacked suitcase gaped open on the floor.

"I've been here three weeks and I haven't put anything up," Tammy admitted, following her gaze.

Emily thought of the photo pinned above her bed. Mum and Dad, sunburnt and grinning, a spur-of-the-moment day that now felt like it belonged to someone else.

"Homesick?" she asked.

Tammy's face crumpled and smoothed again. "Is it that obvious?"

"No." She tried a smile and it wobbled. "I just happen to be an expert."

They ended up sitting on the floor with their backs against the bed, a box of squashed biscuits between them. They didn't say much at first. Tammy talked about her little brother and the dog who slept on her bed, and Emily found herself talking about the theme park, the hats, Dad being bored.

Emily didn't make a single joke. Nobody seemed to mind.